Evening star. [volume] (Washington, D.C.) 1854-1972, 1887-09-05
WORK, FATIGUE AND SLEEP.
Why We Slumber-A Chemical Theory

from Science.
In an address to the Anthropological Society Of
Brussels Prof. Leo Errera has given a resume OF
some points In the chemical theory Of Sleep The
phenomena OF sleep have in common with other
vital functions the character OF periodicity. An
examination Of such periodic functions in general
may aid In ascertaining the cause OF sleep. The
respiratory rhythm is regulated by the amount OF
oxygen and carbonic acid In the arterial blood.
When the blood is charged with oxygen the respi.
ratory center momentariy suspendS activity; but
soon the tissues yield their oxygen to the blood
have it replaced by carbon1c acid, and the blood
thus modified acts as an excitant to the respira.
tory center. Ranke has shown that the fatigue
and recovery OF muscles Is due to a similar alter.
nation Of the accumulation and discharge OF Ger
Tain 'fatiguing substances" chief among which is
iactic acid: An injection OF this acid into flesh
muscle renders 1t incapable OF work; washing the
acid out restores the activity.
Cannot sleep be explained by similar chemical
Ineory? Preyer has extended the views OF BinZ,
Ooerstelner, and others (who all agree in making
the accumulation OF certain products OF fatigue
eIntudi;agSst0te-the cause OF Sleep by calling
an such fauguing products OF activity .'pono-
gems" These accumulate in walking life, are
readily oxidizable and absorb the oxygen intended
!or glands, muscles, and nerve centerS until ac-
the ponogens are DESTROYED by oxidation, slight
eAcltatlon Is sufficient TO arouse the centerS and
waking life begins. Among the ponogens Preyer
counts Tactic acid the chief, but the experiment
TAI demonstration OF this has been unsuccessful,
and the theory, accordingly not generally adopted.
since these researches Armand Gautier has
Iouhu In the human body a series OF five organic
bases akin to creatine, creatinine, and xanthine,
ana calls them ''leucOmaines" and 'ptomaineS.'
Inc physiological properties of these substances
are narcotic, fatlguing. and sometimes lead 10
vomiting. This Is just what the chemical theory
requires. The periodicity OF sleep would be ex-
pialned by the conservation OF energy being APP
plcaDle 10 all bodily activity; work must be fol-
lowed by repair; life is a SLOW suicide. There is.
moreover, reason to believe that the action OF
these leucomaines is a direct one upon the brain;
IL IS direct intOxication OF the brain centerS
A theory or sleep must take account OF three
factors-work, fatigue, and sleep. The chemical
tneOry satisfies these demands. All work, muScu-
lar or cerebral, produces waste products. These
accumulate make work more and more difficult
TINS Is fatigue. As the process continues. the
waste products, notably the leucomaines. intoNi-
cate the higher nerve centers gust as dose OF
morphine does, and render them Incapable OF ac-
ton; that is sleep. The picture is, however, much
more complex. There is a constant struggle
against fatigue, which for time, by dint OF hard
work shown in increased secretions and so on,
may succeed. We probably never arrive at the
extreme limit OF work: the sensation OF fatigue
lhtervenes TO prevent such disaster. Fatigue,
as Is well known, may extend from muscle TO
nerve aud from nerve TO nerve center We may
be very tired from repeatedly lifting a weight and
not be sleepy, and may be generally sleepy with
out any considerable local fatigue. One is peri
pheral, the other central As the waste products
become more and more sluggish, until the time
comes when the ordinary stimulation no longer
afOuSeS them. and we sleep. Partial sleep can be
similarly eXpla1ded. The centerS go to sleep In a
hlerarch1cal order, the highest serving the most
delicate function going first. In waking, the re-
verse Is the case; the motor centers may be
asleep While the intellectual centcrS are awake.
In somnambulism the latter may be asleep while
the former are awake.
The depth OF sleep. according to this theory,
ought 10 be proportioned to the number OF cor
IDEAL molecules In combination with the leuco-
malnes. In the beginning or sleep these are abun-
dant, the cerebral cells inactive, and a cOmblna-
v Is m n "
number OF combinations IS reached, and steep Is
deepest. From here on, the leucOlnaineS are
gradually eliminated and destroyed, and sleep
should decrease wit a decreasing intensity.
kOhlschutter'S experiments on the intensity OF
Seep, as tested by the noise necessary to awake
TIE patient, gives the curve for the intensity Of
Sleep corresponding to what We should expect by
our theory. Variations In sleep, caused by an eX-
cess of work, &C., are evidently similarly eXplicabe
In short fatigue Is poison for which sleep is the
normal antid0te.
This theory maintains a. that the activity OF all
the uSsueS tdnd primarily OF the TWO most active,
the nervous ana Muscular gives rise TO substances
more or less allied to aikaloidS, the leucomaines;
~ that these induce fatigue and sleep; 81 that on
walin-, II the body is reste1, these substances
have disappeared.
TO complete the demonstration OF these state
ments much careINl experimentation is necessary
Dut the facts as far as they go make ii probable
that the chemical theory OF sleep Will gain in
strength with our knowledge.